Synthesis, pharmacological activity evaluation and molecular modeling of new polynuclear heterocyclic compounds containing benzimidazole derivatives
作者:Fatma A. Bassyouni、Tamer S. Saleh、Mahmoud M. ElHefnawi、Sherein I. Abd El-Moez、Waled M. El-Senousy、Mohamed E. Abdel-Rehim
DOI:10.1007/s12272-012-1204-6
日期:2012.12
Novel heterocyclic compounds containing benzimidazole derivatives were synthesized from 2-(1Hbenzimidazol-2-yl) acetonitrile (1) and arylhydrazononitrile derivative 2 was obtained via coupling of 1 with 4-methyl phenyldiazonium salt, which was then reacted with hydroxylamine hydrochloride to give amidooxime derivative 3. This product was cyclized into the corresponding oxadiazole derivative 4 upon reflux in acetic anhydride. Compound 4 was refluxed in DMF in the presence of triethylamine to give the corresponding 5-(1H-benzimidazol-2-yl)-2-p-tolyl-2H-1,2,3-triazol-4-amine 6. Treatment of compound 6 with ethyl chloroformate afforded 2,6-dihydro-2-(4-methylphenyl)-1,2,3-triazolo[4″,5″-4′,5′]pyrimido[1,6-a]benzimidazole-5(4H)-one (8). 1,2-bis(2-cyanomethyl-1H-benzimidazol-1-yl)ethane-1,2-dione (10) was synthesized via the condensation reaction of 2-(1H-benzimidazol-2-yl) acetonitrile (1) and diethyloxalate. The reactivity of compound 10 towards some diamine reagents was studied. The in vitro antimicrobial activity of the synthesized compounds was investigated against several pathogenic bacterial strains such as Escherichia coli O157, Salmonella typhimurium, E. coli O119, S. paratyphi, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus. The results of MIC revealed that compounds 12a–c showed the most effective antimicrobial activity against tested strains. On the other hand, compounds 12a, b exhibited high activity against rotavirus Wa strain while compounds 12b, c exhibited high activity against adenovirus type 7. In silico target prediction, docking and validation of the compounds 12a–c were performed. The dialkylglycine decarboxylase bacterial enzyme was predicted as a potential bacterial target receptor using pharmacophorebased correspondence with previous leads; giving the highest normalized scores and a high correlation docking score with mean inhibition concentrations. A novel binding mechanism was predicted after docking using the MOE software and its validation.
从2-(1H-苯并咪唑-2-基)乙腈(1)合成了含有苯并咪唑衍生物的新型杂环化合物,苯基肼腈衍生物2通过将1与4-甲基苯基二氮盐偶合得到,随后与盐酸羟胺反应生成酰肟衍生物3。该产物在醋酸酐中回流环化为相应的噁二唑衍生物4。化合物4在三乙胺存在下,在DMF中回流,得到相应的5-(1H-苯并咪唑-2-基)-2-p-甲苯基-2H-1,2,3-噁唑-4-胺6。将化合物6与氯乙酸乙酯反应,得到2,6-二氢-2-(4-甲基苯基)-1,2,3-噁唑[4″,5″-4′,5′]嘧啶[1,6-a]苯并咪唑-5(4H)-酮(8)。通过2-(1H-苯并咪唑-2-基)乙腈(1)与二乙氧基草酸的缩合反应,合成了1,2-二(2-氰基甲基-1H-苯并咪唑-1-基)乙烯-1,2-二酮(10)。研究了化合物10对一些双胺试剂的反应性。合成化合物的体外抗微生物活性被研究,对多种致病细菌株如大肠杆菌O157、沙门氏菌鼠伤寒、E. coli O119、S. paratyphi、铜绿假单胞菌、金黄色葡萄球菌、单核细胞增生李斯特菌和蜡样芽胞杆菌进行了测试。MIC的结果表明,化合物12a–c对测试的菌株表现出最有效的抗微生物活性。另一方面,化合物12a、b对轮状病毒Wa株表现出高活性,而化合物12b、c对7型腺病毒表现出高活性。对化合物12a–c进行了计算机靶点预测、对接和验证。预测二烷基甘氨酸脱羧酶作为潜在的细菌靶受体,通过与以前的先导药物的药效团基础对应,给出了最高的标准化评分和与平均抑制浓度的高相关对接评分。在使用MOE软件进行对接及其验证后,预测了新的结合机制。